1. Field of the Invention
The present invention relates to a mounting structure of electronic components and a mounting method thereof, and more particularly, to a mounting structure of electronic components and a mounting method thereof capable of efficiently and reliably mounting electronic components on a film substrate.
2. Description of the Related Art
A conventional mounting structure and mounting method of electronic components will be described with reference to FIG. 4. A film substrate 31 made of heat-resistant resin, such as polyimide, is provided, and a positioning hole 33 into which an electronic component 32, which is a chip component, is inserted is formed in the film substrate 31 by punching.
In addition, conductive patterns 34 are formed on a lower surface of the film substrate 31, and the conductive patterns 34 have a pair of electrode pads 34a and 34b which protrudes from an inner surface of the positioning hole 33 toward the inside thereof.
Further, the electronic component 32 has a pair of terminal parts 32a and 32b to be electrically connected to the pair of electrode pads 34a and 34b, respectively, on the left and right sides thereof.
A mounting method of electronic components using the film substrate 31 and the electronic component 32 having the above-mentioned structure will be described. First, soldering paste 35 is coated on each of the pair of electrode pads 34a and 34b which protrude toward the inside of the positioning hole 33.
After that, the electronic component 32 is inserted into the positioning hole 33 of the film substrate 31, whereby the electronic component 32 is positioned in the positioning hole 33, and the terminal parts 32a and 32b come in contact with the pair of electrode pads 34a and 34b, respectively.
Then, when the pair of electrode pads 34a and 34b is partially heated or the entire film substrate 31 is passed through a high-temperature furnace, the soldering paste 35 is fused so that the pair of electrode pads 34a and 34b is electrically connected to the electronic component 32. Next, when the fused soldering paste 35 is cooled, the soldering paste 35 is solidified so that the electronic component 32 is fixed into the positioning hole 33.
The above-mentioned structure and method are described in Japanese Unexamined Patent Application Publication No. 9-139561.
However, in the above-mentioned conventional mounting structure and mounting method of electronic component, since the electrode pads 34a and 34b are heated in order to fuse the soldering paste 35, the film substrate 31 should have high heat resistance, which causes an increase in manufacturing costs.
To solve the above-mentioned problem, an inexpensive film substrate 31 not having high heat resistance can be used by using a conductive adhesive instead of the soldering paste 35. However, since the conductive adhesive is also expensive, it is difficult to decrease manufacturing costs.